you2 wrote:
Is it my imagination or do both the ze have noticeably better bokeh than the old c/y ?

The new ZE/35/1.4 has the best bokeh as its undercorrected spherical-aberration design trades-off having more haze/less contrast/sharpness wide open to f2.8, for smoother bokeh and the slow focus transition/falloff of objects in the bokeh which retain shape longer further away from focal plane. Read Zeiss CLN35 DOF and Bokeh article on this which explains this behavior. This behavior is very different from other Zeiss lenses. You can see this in the red dogwood flower shot. Objects in the background behind the flower still retain basic shape but are smoothly blurred while the old 35/1.4 does what a normally corrected lens does and just blurs those objects and basic shape is not retained as well as so it is harder to determine what that background object is.
You would also see this behavior in portraits which Ajay has posted to the 35/1.4 thread. The new 35/1.4 shot wide open renders the front of the face and back towards the ears with similar sharpness with the blur transition being very slow and smooth. Whereas the old 35/1.4 acts more like any other zeiss lens as it is very sharp and no haze at the front of the face and then quickly transitons and focus starts falling off very abruptly and without retaining shape in objects further away from the focus plane like the ears which would be much more blurred, with less retained shape. Obviously, the new lens is much more flattering for beauty and more flattering portraits which is why Zeiss designed the lens this way. You probably would not want this lens and would want the old 35/1.4 if you were taking a portrait of an old person on the street where you wanted to show every wrinkle and detail of their face without any softening effect.
Hope that description makes sense.

You can see in the shots which were shot with all three 35's, that the ZE35/1.4 and 35/2 both handle harsh high contrast areas better, less likely to blowout. In less contrasty light the old 35/1.4 has bokeh which is less contrasty and less hardly-defined than the 35/2 and the ZE 35/1.4 ( when its stopped down). This is similar to the difference between 50/1.4 P bokeh and 50MP bokeh.

The difference in subject isolation and 3-d between the new ZE 35/1.4 and the old C/Y 35/1.4 depends on your definition of 3-d and your preference on either obliterating the shape of objects in the background or keeping their basic shape and just blurring them a bit. Like in one of Ajay's nice portrait shots, you can see the green hedge in the background with a lot more basic form and detail of each leaf but blurred a bit so that it is nice and smooth. The old 35/1.4 would obliterate the basic shape of the leaves in the hedge and you would get more of just a green blurred blob like any fast normally SA corrected lens which you may or may not like more.Depends if you want people to make out what is in the background or not.

About 3-d, I would think that a fast focus transitioning lens like the old 35/1.4 would give you more chances of getting the 3-d look compared to a slower transtioning lens like the new 35/1.4. I think the mailbox shots with the ivy show the old 35/1.4 having more 3-d pop than the new 35/1.4.

Just my $0.02 and I want people to know that I like the new 35/1.4 and might end up getting it one day to join my other two Zeiss 35's to use for beauty portraits and flower/garden shots.
Because of huge cost and weight differences and different rendering strengths/behavior, no one zeiss 35 design can be said to be the best. Which one you choose is a personal decision.

I don't know about sharpness, but the Zeiss almost certainly has better boke. It is also a much more expensive lens, so that is not really surprising. The Nikkor is pretty neat though. I could imagine owning both.

I'd love to see a comparison of all the the available 35mm f1.4 lenses, including the new Samyang...I might swap to another 35/1.4 lens if I knew there was a better one...Have to say those Zeiss pics are very impressive so i'm leaning that way at the moment